Avatar images are missing in email notifications

Email notifications are not including the profiles avatar in Cloud instances, as shown below:

Steps to Reproduce

1. Create a user
2. Add an avatar to it (tested with the attached image jira_logo_landing.png)
3. Enable notifications for own changes
4. Create an issue
5. Check notification for this operation

Expected Outcome

• After issue is created, the notification includes correctly the avatar

Actual Outcome

• The notification does not include it.